Why is PING so popular? Recently, the most discussed topic on-chain is the PING under the x402 protocol, with a bunch of people drawing parallels to the Bitcoin inscription craze in 2023. To be honest, this comparison is not unfounded—there are indeed similarities, and the direction of subsequent evolution may also be consistent. The "twin logic" of the two systems First, let's see how Bitcoin inscriptions work. Users send transactions to the BTC mainnet, occupying UTXO, but the Bitcoin mainnet itself cannot determine which transaction counts as a valid inscription. At this point, the Ordinals protocol comes into play - it acts like a referee, scanning on-chain transactions and determining what constitutes a true inscription according to rules like "First is First." What is the gameplay of PING?